Hardness and compression behavior of niobium carbide. Issue 2 (3rd April 2017)

• Record Type: Journal Article
• Authors: Liu, Fangming; Liu, Pingping; Peng, Fang; Liu, Jing; He, Duanwei
• Is Part Of: High pressure research. Volume 37:Issue 2(2017)
• Page Start: 244
• Page End: 255
• Publication Date: 2017-04-03
• Subjects: Hardness -- compression behavior -- Nbc -- binderless -- hard material; High pressure (Science) -- Periodicals; High pressure (Technology) -- Periodicals; 536.41
• DOI: 10.1080/08957959.2017.1297810
• Languages: English
• ISSNs: 0895-7959

Abstract

ABSTRACT: We report the combined experimental and theoretical investigations on high pressure structural stability of niobium carbide (NbC). The compressibility of NbC has been measured using angle-dispersive synchrotron X-ray diffraction in a diamond anvil cell (DAC) at room temperature and high pressure (up to 38.0 GPa), complemented with first-principles density-function theory calculations. The results imply that NbC shows bulk modulus of K 0 = 281 (6) GPa with a pressure derivative K 0 ′ = 6.2 (1.5) for its strong covalent bonding. In addition, indentation testing on the well-sintered bulk NbC obtained at 5.0 GPa/1400°C yielded a Vickers hardness of 19.2 GPa and fracture toughness of 7.7 MPa m 1/2 at applied load of 10 kgf, demonstrating that binderless NbC prepared under high pressure should be a prospective hard material.